From: Marek Vavruša <marek.vavrusa@nic.cz>
Date: Sat, 18 Apr 2015 21:30:16 +0000 (+0200)
Subject: lib/generic: implemented deletion for pack
X-Git-Tag: v1.0.0-beta1~237^2~5
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f5502f48a3a9cded75757e2f2d243add0bf8321e;p=thirdparty%2Fknot-resolver.git

lib/generic: implemented deletion for pack
---

diff --git a/lib/generic/pack.h b/lib/generic/pack.h
index 49f9a0c30..33e889c53 100644
--- a/lib/generic/pack.h
+++ b/lib/generic/pack.h
@@ -43,6 +43,9 @@
  *          it = pack_obj_next(it);
  *      }
  *
+ *      // Remove object
+ *      pack_obj_del(pack, U8("jedi"), 4);
+ *
  *      pack_clear(pack);
  *
  * \addtogroup generics
@@ -80,7 +83,7 @@ typedef array_t(uint8_t) pack_t;
 	array_reserve_mm((pack), (pack).len + (sizeof(pack_objlen_t)*(objs_count) + (objs_len)), (reserve), (baton))
 /** Return pointer to first packed object. */
 #define pack_head(pack) \
-	&((pack).at[0])
+	((pack).len > 0 ? &((pack).at[0]) : NULL)
 /** Return pack end pointer. */
 #define pack_tail(pack) \
 	&((pack).at[(pack).len])
@@ -122,6 +125,26 @@ static inline int pack_obj_push(pack_t *pack, const uint8_t *obj, pack_objlen_t
 	return 0;
 }
 
+/** Delete object from the pack
+  * @return 0 on success, negative number on failure
+  */
+static inline int pack_obj_del(pack_t *pack, const uint8_t *obj, pack_objlen_t len)
+{
+	uint8_t *endp = pack_tail(*pack);
+	uint8_t *it = pack_head(*pack);
+	while (it != endp) {
+ 		uint8_t *val = pack_obj_val(it);
+ 		if (pack_obj_len(it) == len && memcmp(obj, val, len) == 0) {
+ 			size_t packed_len = len + sizeof(len);
+ 			memmove(it, it + packed_len, endp - it - packed_len);
+ 			pack->len -= packed_len;
+ 			return 0;
+ 		}
+ 		it = pack_obj_next(it);
+ 	}
+ 	return -1;
+}
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/tests/test_pack.c b/tests/test_pack.c
index 27c09bffd..f5ad501cd 100644
--- a/tests/test_pack.c
+++ b/tests/test_pack.c
@@ -27,8 +27,9 @@ static void test_pack_std(void **state)
 	pack_init(pack);
 	assert_int_equal(pack.len, 0);
 
-	/* Push without reservation. */
+	/* Push/delete without reservation. */
 	assert_int_not_equal(pack_obj_push(&pack, U8(""), 1), 0);
+	assert_int_not_equal(pack_obj_del(&pack, U8(""), 1), 0);
 
 	/* Reserve capacity and fill. */
 	assert_true(pack_reserve(pack, 10, 10 * 2) >= 0);
@@ -48,6 +49,10 @@ static void test_pack_std(void **state)
 		count += 1;
 	}
 
+	/* Delete */
+	assert_int_not_equal(pack_obj_del(&pack, U8("be"), 2), 0);
+	assert_int_equal(pack_obj_del(&pack, U8("de"), 2), 0);
+	assert_int_equal(pack.len, 9*(2+2)); /* 9 objects, length=2 */
 
 	pack_clear(pack);
 }